Government regulations require that the exhaust emissions of small internal combustion engines be reduced. One way to reduce the exhaust emissions of small internal combustion engines is to use a catalytic converter to treat the exhaust emissions of the engine. In small internal combustion engines, it may be desirable to combine the catalytic converter with a muffler into a single, compact unit.
Catalytic converters or catalytic mufflers can greatly increase the cost of a small internal combustion engine, especially due in part to the cost of the catalyst used in the catalytic converter. Therefore, it is desirable to decrease the cost of the catalytic converters to the greatest extent possible.